Physiology Flashcards
What are type 1 pneumocytes?
Single layer of alveoli wall. Aids diffusion
What are type 2 pneumocytes?
globous. secret fluid (surfactant) to moisten alveoli and prevent sticking together.
Where are sperms matured and learn to swim?
Epididymis
Function of seminal vesicles
provide sperms nutrients e.g. sugar for respiration
secrete mucus to protect sperm
Function of prostate
add alkali fluids to neutralise vaginal acid, mineral ions
Where is testosterone produced?
Interstitial cells
Where is FSH produced?
Anterior pituitary
What does testosterone, FSH, LH stimulate in spermatogenesis
FSH –> meiosis of primary spermatocyte
LH –> testosterone
Testosterone –> meiosis 2
Where is the origin of spermatogenesis
germinal epithelial
What is produced by type 2 pneumocytes?
Pulmonary surfactant
Which factors could cause emphysema?
a) air pollution
b) genetic predisposition
c) tobacco smoke
all above
Which organ in the human body secretes lipase, protease and amylase?
pancreas
In which process is surface area of key importance for humans?
a) reabsorption of glucose in the proximal convoluted tubule
b) release of surfactants by type 1 pneumocytes
c) display of antibodies by red blood cells
d) secretion of enzymes by villi of the small intestine
a
Which is the correct statement concerning HIV and AIDS?
a) all HIV patients have AIDS
b) HIV and AIDS are transmitted on the sex chromosomes
c) All AIDS patients have HIV
d) HIV and AIDS neutralize antibodies
c
What happens first when a neurotransmitter binds to a postsynaptic neuron?
a) ions diffuse
b) electrophoresis begins
c) Ca2+ channels open
d) repolarisation
a
Describe how the hormone leptin helps to prevent obesity
Produced in adipose tissue
(reject produced by pituitary)
target cells: hypothalamus
inhibits appetite
Explain the effect of neonicotinoid pesticides in insect synapses in the central nervous system
Bind to acetylcholine receptors Irreversible binding prevents acetylcholine binding Block transmission from central nervous system Cause paralysis
Outline the process of inspiration in humans
Volume of lungs increases
Pressure: decreases (air enters lungs due to increased pressure outside of body)
Diaphragm: contracts + downwards, pushing abdomen wall out. Abdomen wall relax
External intercostal muscles: contract, pulling ribcage upwards and outwards
Internal: relax (Expiration: Internal contracts, pulling ribcage inwards and downwards)
Describe the functions of valves in the mammalian heart
Prevent backflow
Open valves allow blood to flow thru
Opening and closing of valves control timing of blood flow during cardiac cycle
Closed semilunar valves allow ventricle to fill with blood/allow pressure in ventricles to rise
Valves open when pressure is higher upstream
Where does mitosis in oogenesis occur?
germinal epithelial
What is mitosis 1 in oogenesis stimulated by?
FSH
Which stage does meiosis 1 in oogenesis stop?
prophase 1
What does secondary oocyte produce? why is it produced?
1st polar body; cytoplasm divide unequally
What does meiosis 1 produced in oogenesis?
secondary oocyte + 1st polar body
Which stage does meiosis 2 stop in oogenesis?
metaphase 2
What’s the function of LH?
Ovulation
When’s meiosis 2 completed in oogenesis?
after fertilisation
What does empty follicles become after fertilisation of ovum?
corpus lutuem
What does corpus luteum produce?
progesterone
Describe the steps of fertilisation.
- Acrosome reaction: enzymes in sperm head digest zona pellucida
- plasma membrane of egg and sperm fuse
(Stimulates Ca2+ release in the egg; meiosis 2 completed) - Cortical reaction: Cortical granules fuse with egg plasma membrane
1, 2, 3 prevent polyspermy
Nucleus of sperm stays in the egg cytoplasm
What is a fertilised egg called?
zygote
What does a zygote develop into?
morula
What does morula develop into?
blastocyst
Where is the blastocyst implanted?
endometrium
When is HCG released?
After the implantation of blastocyst in the endometrium
What does HCG stimulates?
Stimulate corpus luteum in the ovary to secrete progesterone and estrogen